2*1=1/2+1/(2+1)(1+A)=2/3
A=1
2007*2008=1/(2007×2008)+1/(2008×2009)
=1/2007-1/2008+1/2008-1/2009
=1/2007-1/2009
=2/(2007×2009)
=2/4032063
2*1=1/2+1/(2+1)(1+A)=2/3
A=1
2007*2008=1/(2007×2008)+1/(2008×2009)
=1/2007-1/2008+1/2008-1/2009
=1/2007-1/2009
=2/(2007×2009)
=2/4032063